Structural basin in W Texas and SE New Mexico. Includes Midland, Delaware, and Marfa basins. Indexed with states or regions as applicable. Added to Thesaurus in 1981.
Before 1998, also search Permian-Triassic; (Permian AND Triassic AND (stratigraphic boundary or boundary)). This term has multiple hierarchies. Added to Thesaurus in 1998.